The wave motif is taken from Katsushika Hokusai (1760-1849), a Japanese painter and wood engraver, who is an exceptional example of the Ukiyo-e, or "pictures of the floating world" (everyday life), school of printmaking.  He was an aknowledged influence on the french impressionists Claude Monet, Edgar Degas, and Henri Toulouse-Lautrec, who collected his work.